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Faking a JPEG

ty-penguin.org.uk

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Re: Faking a JPEG

#21

Post by gregdeon »

puttycat wrote: post #18

> compression tends to increase the entropy of a bit stream. Does it? Encryption increases entropy, but not sure about compression.

Yes: the reason why some data can be compressed is because many of its bits are predictable, meaning that it has low entropy per bit.

Re: Faking a JPEG

#22

Post by Modified3019 »

Love the effort.

That said, these seem to be heavily biased towards displaying green, so one “sanity” check would be if your bot is suddenly scraping thousands of green images, something might be up.

Re: Faking a JPEG

#23

Post by BlaDeKke »

maxbond wrote: post #19
dheera wrote: post #6

> So the compressed data in a JPEG will look random, right? I don't think JPEG data is compressed enough to be indistinguishable from random. SD VAE with some bits lopped off gets you better compression than JPEG and yet the latents don't "look" random at all. So you might think Huffman encoded JPEG coefficients "look" random when visualized as an image but that's only because they're not intended to be visualized th…

Encoded JPEG data is random in the same way cows are spherical.

Cows can be spherical.

Re: Faking a JPEG

#26

Post by recursive »

Modified3019 wrote: post #22

Love the effort. That said, these seem to be heavily biased towards displaying green, so one “sanity” check would be if your bot is suddenly scraping thousands of green images, something might be up.

Mission accomplished I guess

Re: Faking a JPEG

#27

Post by creatonez »

EspadaV9 wrote: post #7

I like this one https://www.ty-penguin.org.uk/~auj/spigot/pics/2025/03/25/fa... Some kind of statement piece

For the full experience:

Firefox: Press F12, go to Network, click No Throttling > change it to GPRS

Chromium: Press F12, go to Network, click No Throttling > Custom > Add Profile > Set it to 20kbps and set the profile

Re: Faking a JPEG

#28

Post by russelg »

bschwindHN wrote: post #3

You should generate fake but believable EXIF data to go along with your JPEGs too.

They're taking the valid JPEG headers from images already on their site, so it's possible those are already in place.

Re: Faking a JPEG

#29

Post by whatsupdog »

cAtte_ wrote: post #13
derefr wrote: post #12

> It seems quite likely that this is being done via a botnet - illegally abusing thousands of people's devices. Sigh. Just because traffic is coming from thousands of devices on residential IPs, doesn't mean it's a botnet in the classical sense. It could just as well be people signing up for a "free VPN service" — or a tool that "generates passive income" for them — where the actual cost of running the software, is t…

sounds like a botnet to me

Botnet with extra steps.

Re: Faking a JPEG

#30

Post by EspadaV9 »

myelinsheep wrote: post #24
EspadaV9 wrote: post #7

I like this one https://www.ty-penguin.org.uk/~auj/spigot/pics/2025/03/25/fa... Some kind of statement piece

Anything with Shakespeare in it?

Looks like he didn't get time to finish

https://www.ty-penguin.org.uk/~auj/spigot/pics/2025/03/25/fa...

Terry Pratchett has one I'd like to think he'd approve of. Just a shame I'm unable to see the 8th colour, I'm sure it's in there somewhere.

https://www.ty-penguin.org.uk/~auj/spigot/pics/2025/03/25/fa...

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